Industrial clock controller

industrial-clock controller 171 At the same time, bistable IC5 toggles and causes the bridge circuit composed of T2. . .T8 to reverse the motor polarity every 60 seconds. Depending on the type of clock you have, the transformer secondary voltage may have to be selected to supply about 0.7 times the normal operating voltage of the clock motor. Furthermore, the bridge circuit as shown should not be made to operate at voltages in excess of 30 V, while the maximum current is about 250 mA. There is only one adjustment point in the circuit, namely Pi, which should be set to achieve maximum sup- pression of mains borne noise; if this can not be checked, the preset may Nowadays, most clocks and watches are quartz controlled and, therefore, accurate to within a few seconds a year. Older type electric clocks, par- ticularly those used in large groups in warehouses, department stores, factories, railway stations, and so on, were centrally controlled and synchronized. This synchronization was...